HMRC recognition
Two registrations, two bodies, two applications. Charities routinely complete the first and assume the second happened.
Recognition requires the organisation to be established for charitable purposes, to be under the jurisdiction of a UK court, to be registered where required, and to be managed by fit and proper persons. Without it there is no Gift Aid and no charitable tax relief.
Apply as soon as you are registered — see registering with HMRC. Donations received before recognition may still be claimable afterwards within the time limits.